Pelecolipeurus gen. nov.

Type species.

Pelecolipeurus fujianensis sp. nov.

Diagnosis.

Pelecolipeurus gen. nov. keys to Reticulipeurus Kéler, 1958, in the key of Gustafsson et al. (2020b). Species of Pelecolipeurus can be separated from Reticulipeurus and all other members of the Oxylipeurus -complex by the following combination of characters: frons rounded to slightly flattened (Figs 3, 17); dorsal pre-antennal suture present, transversal, but not reaching lateral margins of head (Figs 3, 17); mms gathered into a single sublateral bunch (Figs 1, 2, 15, 16); male tergopleurites II-VII medianly interrupted and intertergal sclerites absent (Figs 1, 15); male tergopleurites IX-XI fused to form single plate (Figs 1, 15); female tergopleurites IX-XI fused laterally, but not medianly, forming two distinct plates (Figs 2, 16); male subgenital plate of unique shape, with lateral extensions at base of stylus (Figs 7, 21); stylus subterminal, elongated to reach beyond distal margin of abdomen (Figs 7, 21); female vulval margin narrowly concave, without lateral accessory vulval plates (Figs 8, 22); male genitalia very long, reaching anteriorly to abdominal segment III (Figs 5, 19); denticulate genital sac present in male genitalia (Figs 5, 19); male genitalia symmetrical, with parameres present, mesosome dominated by large gonopore (Figs 6, 20).

Description.

Both sexes. Male longer than female (Table 1). Head longer than wide, frons rounded to slightly flattened (Figs 3, 17). Dorsal pre-antennal suture present, but often not well-defined and visible as pale band across head; suture not reaching lateral margins of head. Interior thickenings of pre-antennal head present as double, undulating carinae anterior to suture. Head chaetotaxy as in Figs 3, 17; mds may be absent in female; s2 (?) located median to s1; s5 absent; s6-8 present; mts3 only temporal mesoseta, but os may be longer than pos and mts1-2 in males. Antennae sexually dimorphic, with male scape and pedicel elongated and swollen compared to female (cf. Figs 3, 4, 17, 18); male flagellomere I with distal, finger-like extension and intensely scaly inner surface (Figs 3, 17). Temples rounded, somewhat bulging. Thoracic and abdominal segments as in Figs 1, 2, 15, 16. Legs II and III much longer than legs I; coxae I-II close together. Meso- and metasterna fused. Metepisternum long, reaching almost to mesometasternum. Pronotum with lateral and posterior setae; pteronotum with microsetae in antero-lateral corners and short seta submedianly in distal half; mms in single sublateral bunch; mths and mtrs roughly dorsal. Tergopleurites II-VII in both sexes medianly interrupted; male tergopleurites IX-XI fused into a medianly continuous plate; female tergopleurites IX-XI fused laterally, but not medianly (Figs 2, 16). Male subgenital plate with lateral extensions in distal section (Figs 7, 15); stylus slender, elongated, tapering, attached subterminally and extending beyond distal margin of abdomen. Female subgenital plates reduced to near vulval margin; exact extent of these often not clearly visible. Leg chaetotaxy as in Figs 9-14.

1 N = 15 for TL; N = 18 for AW. 2 N = 24 for TL; N = 29 for PTW; N = 38 for AW.

Male. Male scape, pedicel and flagellomere I modified compared to female. Male genitalia very long (Figs 5, 19), with basal apodeme reaching to at least abdominal segment III, but diffuse anteriorly. Genital sac present, irregularly, but densely denticulate (Figs 6, 20). Distal third of basal apodeme with irregularly thickened lateral margins articulating with parameral heads. Mesosome simple, with central sclerite on ventral surface associated with 2-3 sensilla; three additional sensilla in oblique, distally divergent rows lateral to this sclerite. Gonopore large, dominating mesosome. Parameres short, slender, pst1 sensilla in distal third, pst2 microsetae, situated more or less apically.

Female. Vulval margin deeply and narrowly concave (Figs 8, 22). Three sets of genital setae: long, slender vms, the more median setae shorter than the more lateral setae; short, slender or lightly stout vss in median part of vulval margin; single seta on each side situated further submarginally and apart from vss. Subvulval sclerites present, slender and elongated, reaching to vulval margin.

Host distribution.

Presently known only from tragopans (genus Tragopan Cuvier, 1829), Phasianidae, Galliformes . Some specimens from other hosts (see below) may represent stragglers or contaminations.

Geographical range.

All known species are from China or the Himalayas, corresponding roughly to the combined range of the known hosts.

Etymology.

The name Pelecolipeurus is derived from " pélekus ", Greek for "two-headed axe" and the traditional name for long slender lice, Lipeurus Nitzsch, 1818. This refers to the shape of the male subgenital plate.

Remarks.

Gustafsson et al. (2020a) tentatively included Lipeurus longus Piaget, 1880, in Reticulipeurus Kéler, 1958, following von Kéler (1958) and Złotorzycka (1966). They noted that they had not examined any specimens and that this placement was doubtful, based on the illustrations published by Clay (1938a) and von Kéler (1958). The examined collection at NNHM includes two different species belonging to the same morphological group as L. longus and these are sufficiently different morphologically from all other members of the Oxylipeurus -complex that the erection of a separate genus is warranted.

Unfortunately, no specimens from the type host of Lipeurus longus were found at NNHM and no specimens of this species have been examined from other collections. A lectotype and five paratypes are available at the Natural History Museum, London (NHML), but we had no opportunity to examine or borrow these. A photo of the lectotype female at the NHML homepage (https://data.nhm.ac.uk/dataset) confirms that this species belongs to Pelecolipeurus, but is insufficiently detailed to compare adequately with the specimens we have examined at the NNHM. Only two modern illustrations of L. longus have been published (Clay 1938a; von Kéler 1958), both of which depict the ventral view of the distal end of the male abdomen. Allowing for individual variation and differences in illustration techniques, we cannot separate the specimens illustrated in these publications from specimens we have seen from Tragopan temminckii (Gray, 1831) (see below) and these specimens are here tentatively considered conspecific with L. longus; however, this will need to be confirmed by comparison with type specimens of L. longus and a re-description of this species.

As the type specimens of L. longus could not be examined, we select the species that could be examined as the type species of Pelecolipeurus .

Included species.

Pelecolipeurus fujianensis sp. nov. Type host: Tragopan caboti (Gould, 1857).

Pelecolipeurus longus (Piaget, 1880: 370) [in Lipeurus]. Type host: Tragopan satyra (Linnaeus, 1758).